Hello,
this is just a project status update. The program now draws the locations and adds the correct objects and sprites.
I have gone a bit further and have coded "evnt10" too, but this does nothing on the screen, so I will debug/trace it to verify it works fine.
Next will be the "main loop events".
Certainly I had forgotten that the 16 bit values are treated differently on the Z80 with respect to the way we they are on 6809.
As I use 16 bit registers as much as I can, I need to verify that when writting later I do that in reverse order
Blocks and Objects have been easy to port, but sprites with the (bad) trick of pointing to the ROM when out of screen, have been a nightmare.
Besides, adding the "evnt10" the global code exceeds the 32k limit on a 6809 machine. So, it was time to switch to MAP1 (all RAM),
copy there the Basic Interpreter and use the highest part of RAM for the graphics, that way some 7,197 bytes are free now and if it were the case,
I could re-use the DOS area (C000-E5FF) so 9,728 extra bytes. This has to be enough for the total port, I hope!
Right now I have all into RAM, even the ROM, so the ROM trick now overwrites the, otherwise, protected ROM contents
Will add a bit of code to control that in "dline"
I am uploading here two binary files:
- FOGPM3 this one shows graphics in PMODE3 (4 colours)
- FOGPM4 that one uses PMODE4, so only black and white (unless you have artifacts on)
Code: Select all
1 - Load the game and EXEC&HE00, this will show the menu
2 - Pressing any key will show the first location
3 - Any key will show the Objects if any present in that location
4 - Any key will show the sprites for this location, despite the coordinates for the player
will be wrong, they are only correct for the first location
5 - Now you may choose among these options
- 'N' to see Next location
- 'P' to go back to Previous location
- 'Q' to quit the program. The computer will restart to std mode
If you change location, it just goes back to point 3
These files can be loaded into XRoar emulating a CoCo or a Dragon 64k without issues
I will put the files inside VDK and DSK files for people that prefers that way for testing them.
Will upload them later
cheers
pere